For FY16, we have used multi-dimensional NMR, X-ray crystallography, site-directed mutagenesis coupled with isothermal titration calorimetry to study how nucleosomes and histones are recognized by other proteins. We have determined the crystal structure of the chromatosome containing the globular domain of H5 and identified two different binding modes of linker histones, which have implications for the higher-order chromatin structures. We further obtained a new crystal structure of the chromatosome whose packing in the crystal suggests a ladder-like chromatin structure.